Machine for electrically welding chain-links.



G. L. HO-PP.

MACHINE FOR BLEGTBIGALLY WELDING CHAIN LINKS.

Patented Aug. 22, 1911.

8- BHEETS8HEET 1.

APPLICATION FILED 0014, 1909.

G. L. HOFF.

MACHINE FOR ELEGTRIGALLY WELDING CHAIN LINKS.

APPLICATION FILED 0014, 1909.

I 1,001,271 Patented Aug. 22, 1911;

3 SHEETSBHBET 2.

G. L. HOFF.

MACHINE FOR ELEGTRIGALLY WELDING GHAINVLINKS.

APPLICATION FILED OCT. 4, 1909.

Patented Aug. 22, 1911.

3 SHEETSSHEET 3.

lm Mums 32 being applied to a link. Fig. 2 is a section To all whom it"may concern.-

UNITED STATES PATENT OFFICE.

CARLTON L. HOFF SOF YORK, PENNSYLVANIA, ASSIGNOR 'IO STANDARD CHAIN COM- PANY, OF Y ORK, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

- MACHINE FOR EIJECTRICALLY' WELDING CHAIN-LINKS.

Be it known that I, CARLTON L. Horr, a citizen of the United States, residing at York, county of York, and-State of Pennsylvania, have invented-certain new and useful Improvements in Machines for Electrically \Velding Chain-Links; and I- do hereby del clare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this specification, and to the figures and letters of rcferencemarked thereon.

. This invention relates to electric welding and more especially to that branch of the art having for its object the production of welded chain or chain links.

The machine of the present invention is I only semi-automatic in its action,.being deillustrated in Fig. 1.

signed primarily for welding individual links which are successively presented thereto by the attendant who operatesthe-machine, although afterbeing presented and the welding heatproduoed, subsequent ma nipulation to form the weldis automatically performed by the machine itself.

Referring to the accompanying draw ings-Figure 1 isa to -plan view of the machine with the parts 1n the position occupied by them when'the weldingcurrent is in a vertical plane substantially central of the machine with the arts in the position Fig.3 is a-detail sectional plan illustrating the welding elec' trodes and parts associated directly therewith and showing also the forward end of the positioning former. Fig. 4 is a detail sectional elevationof the switch for controlling the primarycircuit of the welding transformer. Fig.5 is a detail perspective view of one of the-electrodes. Fig. 6 is a-similar 'view of the forward end of the positioning former. Fig.7 is a similar view ofthe top former. Fig.8 is a similar view of the bottom former, and Fig. 9 is a-detail sectional view corresponding to :a part of Fig.2, blitwith the positiomn former advanced'to partly form the wolf.- 1

Similar letters ofreference figures indicate like parts.

The working parts ofthe machine in the preferred construction, arepreferably mounted u one metal bedtplate A which is conveniently supported by legs B at such heightthat Specification of Letters Patent. Application filed October 4, 1909. Serial Nth-520,776.

proximate ends of the weldizig in the several:

the-operator may work while- Patented Aug. 22, 1911.

seated in front of'the ma chine. Said working parts of the machine embody Welding or terminal electrodes C adjustably'clamped properly insulated therefrom and the terminals or bearings E are at the forward ends of arms E the latter having a suflicicnt cross-sectional area to avoid resistance losses in the welding circuit.

For swinging the carriers D and electrodes C toward each other, the carriers are provided with rearwardly extending arms D suitably insulated therefrom atdand connected at their rear ends by a relatively heavy spring D said spring being conveniently bridged between brackets or posts d extending downwardly through slots a in 'the bed plate A. In order that-the electrodes will be forced to advance-in unison intermeshing gear-segments'D pivoted on the under face of the bed plate are con-' nected by links D with the rear ends of the arms D.

For separating the carriers and electrodesthe rear ends of the arm D are provided with projections or rollers f adapted to cooperate with oppositely disposed face cams F, on a counter-shaft G journaled in suitablebearings mounted transversely on the rear portion of the bed plate. The shaft G is adapted to be driven through gear wheels 9 from a drive shaft g operated by a belt or other suitable power, there being interposed in the driving connections between said shafts g and G a one revolution clutch H controlled by a lever or treadle h. The electrodes 0 are formed with grooves c, ig. 5, for the reception of the sides of the said electrodes advance or move toward each link and as other they-are adapted to press the open ends of the link together and supply cur" rent for raising said link ends' to the welding heat. Inasmuch as: the one-revolution clutch arrests the movement of the shaft G- when the electrodes are free to advance toward each/other the welding current is applied until the operator again inaugurates the movement of the shaft G by depressing the treadle h. It'is preferred thata switch be employed which opens the primary of the transformer during the initial forward movement of the shaft at eachoperation of the machine and a convenient form of switch is illustrated in Figs. 1 and l. From these two figures'it will be seen that a spiral cam I is mounted on the shaft and when the shaft is at rest the highestportion of the cam rests upon and depresses the movable contacts z' of a switch I which is interposed in the primary circuit in the well understood manner.

In an arrangement such as so far described successive links might be presented to the electrodes when they are retracted or 4 separated, which links will be closed and the welding current supplied for forming welds but, in accordance with the scheme of the present machine provision is made whereby not only may the links be quicklyand accurately positioned by the attendant but during each operation of the machine after a link has been raised to the welding heat, suitable formers will be caused to operate upon the heated weld so as to give the link a correct and accurate form, as well as to insure a perfect union of the metal at that point. I

To enable the attendant to qiiickly and accurately position succeeding links, an adjustable positioning gage K is mounted on a bracket K immediately in front of the welding electrodes, the link engaging face of the gage being properly shaped to receive and position the closed end of the link.

WVhen the closed end of the link is placed in its seat on thegage K its forwardend (open end) may rest upon or within the grooves in the electrodes C, although it is preferred to provide a positioning former which ismovable into and out of position to engage with the inner or open ends of the links. This positioning former (shown in detail in Fig. 6) is provided with a forming groove L and a forwardly projecting supporting surface L7 upon which the open ends of the link may rest and by which they will be supported in proper. 'alinement' for being grasped by the electrodes 0 when the latter advance toward each other.

The supporting .former is retracted by a spring L*- and constitutes a continuation of a cylindrical slide L mounted in the machine head M. At its rear end the slide is provided with an adjustable anti-friction roller or surface L adapted to travel on a cam carried by the shaft G and having a long cam projection-l, a short but somewhat higher cam projection Z, and a recess of depression Z inwhich the anti-friction roller lLLC'QI nes to rest after each movement of the shaft. "Daring the time the link is being positioned by the attendant the anti-friction Y roller L is traveling upon the long camprojection Z, thus affording sufficient time for the attendant to position the link and'for the electrodes to advance and grasp the same before the supporting or positioning former retreats from the position indicated in Fig. 9 to that indicated in Fig. 2.

F or giving complete form to the weld, oppositely movable top and bottom formers N and 0, Figs. 7 and 8, are provided said formers being mounted in vertically movable carriages N and O mounted to slide in ways in the head M and operated by levers N and respectively, connected at their outer ends by a coil spring P and at an intermediate point provided with rollers or projections 91?, 0 adapted to cooperate with edge cams a 0 respectively. The cams are all mounted on the counter-shaft Gr and are so formed and positioned with relation to each other that the'following operations will be performed and in the order named at each revolution of the shaft Gr.

Assuming that the machine has come to rest with a link grasped between the electrodes and the welding current flowing, the attendant observing when the heat has reached the required degree depresses the treadle so as to inaugurate the movement of the shaft G. The movement of the shaft G first breaks the primary circuit of the welding transformer and practically at the same time advances the positioning former L transversely toward the axis of the link aperture into engagement with the end of the link at the welding point, thereby pushing back the metal which tends to -work beyond the end of the link and giving a partial form to the weld. This movement of the positioning former is a quick movement of short duration for the cam projection Z passes away from the rear end of the former slide when the shaft has made a very short angular advance. -The cams n 0 next cause the bottom and top formers to advance, the bottom former being advanced slightly before the top former by the cam 0 and'being held by the concentric surface or dwell of the cam while the top former is advanced so as to shear off any surplus metal at the 'weld and give proper form to the same. During all these movements the welding electrodes have been held advanced by their spring D but immediately upon the completion of the excursions of the top and bottom formers the cams F engage with the rollers f on the arms I D of the electrode carriers and separate said electrodes, thereby allowing the link to drop by gravity or, if the attendant has previously hooked another open link therethrough the link discharged from the machine Wlll be suspended upon the next link to be Welded. The shaft Gr continues its movement and the attendant places the next link position to be-grasped by the electrodes, the positioning former L having in the meantime advanced into proper position for assisting in the-location of the link due to the engagement of the long cam projection Z with the rear end of the former slide. At the instant when the positioning former retreats, owing to its rear end passing into the recess Z the shaft G is 1 brought to rest-by the automatic action of far removed from the sharp curvature of such end to avoid any movement of the link with respect tothe electrodes themselves as the link is being closed and welded. This feature is important inasmuch as practice has demonstrated the desirability of avoiding as far as possible any change in the form of the faces of the electrodes such as would be occasioned by the arcing and cutting action between the links and electrodes when relative movement occurs at their point of contact.-

The electrode carriers being pivotally mounted close together and at points, well forward of the link will cause the electrodes themselves at the points of contact with the link to movein arcs of circles which substantially correspond'tothe arcs of movement of the ends of the link and this arrangement alsoaids in avoiding any relative movement between the links and the electrodes with the result that auniform and perfect contact will be made and maintained between the electrodes and the opposite sides of the link during the link closing and welding operation.

By making the positioning gage K adjustable on its bracket K, links of various lengths may be welded on the same machine without other change in adjustment and it is obvious that, by the simple substitution of other dies or formers links of heavy or light metal may be readily welded, inasmuch as the operating parts of the machine are all adapted for use without change inwelding either heavy or light links.

The machine is designed primarily for welding links which are open at oneend and in this respect, as .well as with respect to certain broad features of construction, it corresponds to the machine of my 1prior application, Serial No. 405,245, filed ecember 5 1907.

Having thus-described my invention, what I' claim as new and desire to secure by Letters Patent of the United States, is

1. Inan electric chain welder, the combination with the welding electrodes movable toward and from each other, of a position-' 5 ing former adapted to engage the outer side I of the link at the welding point and movable transversely toward the axis of the link aperture, means formoving said former out of engagement with the link during the heating of the'latter, and means for moving said former into engagement with the link at the welding point after the heating and link, before the link is released.

2. In an electric chain welding apparatus, the combination with the welding electrodes movable toward and from each other, of a positioning former movable in alinement with the link horizontally into position for trodes, means for withdrawing said positioning former during the heating of the link, and means for again moving said former into engagement with the link at the welding point before the latter is released by the electrodes to press the weld inwardly.

3. In an electric chain welding apparatus, the combination with the welding electrodes movable toward and from each other, to grasp a link and apply the heating current, of a fixed guide and movable positioning former located on opposite sides of the welding electrodes, and means for moving the movable positioning former out of engagement with the link during the heating of the latter.

4. In an electric chain welding apparatus, the combination with the weldin electrodes movable toward and from eac other to rent, of a fixed guide 1n front of said welding electrodes and a movable positioning former in rear of said electrodes between which guide and former the link is positioned, and means for Withdrawing the movable former during the heating of the link.

5. In an electric chain welding apparatus, the combination with the welding electrodes movable toward and from each other to grasp the link and apply the heating cur-.

mounted in front of said electrodes, a positioning former movablymounted in rear of tioning former out of engagement with the link during the heating of the latter, and means for forming the welded joint.- 7 g 6. In an electric chain weldin apparatus, the combination of the electro es movable toward and from each other to grasp a link and apply the welding current, electrode carriers pivotally mounted on arallel axes in proximity to each other an a link supporting guide and a positioning former located on opposite sides of the electrodes, the guide being located a greater distance from guiding a link to be grasped by the elec-' grasp the link and apply the heating cur- .rent, of a positioning guide 'adjustably said electrodes, means for moving the posifor pressing the heated metal inwardly. toward the axis of the aperture through the v the electrodes than the former on the opposite side of said electrodes, whereby the open end of the link to be welded is located remote from the axes of the carrier and the arcs of movement of the cont-act faces of the electrodes and link substantially coincide.

7. In an electric chain welding'machine, the combination with the welding electrodes movable toward and from each other to grasp the link and apply the heating current, of a former movable in alinement with the link being welded to press the weld inwardly, transversely movable formers for giving form to the body of the weld, and

' means for advancing and retracting the first mentioned former prior to the operation of the transversely movable formers.

8. In an electric chain welding apparatus, the combination with the welding electrodes movable toward and from each other to grasp the link and apply the heating current, of top and bottom formers movable toward and from each other, a horizontally movable former, and means for moving the horizontally movable former between the nevi and from the welding point, one of said formers having a pro ecting port-ion forming a support for positioning the link prior to being welded, and means for advancing been raised to a welding heat.

CARLTON L. HOFF.

Witnesses:

ANDREW J. BRENNEMAN, .GRAcE M. DRAYEIL current, ofthree formers movable toward said formers successively after the link has 

